Works across all expression levels, not just the high ones
In the long and difficult human struggle against cancer and immune disease, a Shanghai-based biotech firm has marked a meaningful inflection point — not through a single discovery, but through the convergence of clinical validation, regulatory recognition, and commercial discipline arriving together. Antengene's mid-2025 results suggest that its experimental therapies are reaching patients who had few options left, including those whose tumors resist the treatments medicine currently relies upon most. The story unfolding here is one of a company translating scientific ambition into measurable human benefit, while building the financial foundation to sustain that work.
- ATG-022 earned China's Breakthrough Therapy designation after showing a 40% tumor response rate in gastric cancer patients across all levels of target protein expression — an unusual breadth that could make it useful for far more patients than competing drugs.
- ATG-037 is producing durable responses in melanoma patients whose cancers had already defeated the most advanced immunotherapies available, with some patients remaining stable for over 32 months — a result that challenges the assumption that checkpoint-resistant disease is a dead end.
- XPOVIO revenue surged 70.6% even as the company slashed sales and administrative costs by roughly a third, signaling that commercial operations are becoming leaner and more effective rather than simply louder.
- A new frontier is opening: ATG-201, designed to treat autoimmune diseases, is entering human trials in Q4 2025, backed by primate safety data and a proprietary platform the company is actively seeking partners to develop.
- With RMB 794 million in cash and multiple programs approaching proof-of-concept readouts, the company is positioned to answer its most important clinical questions without immediately returning to capital markets.
Antengene, listed in both Shanghai and Hong Kong, released first-half 2025 results that captured a company advancing on several fronts simultaneously — clinical, regulatory, and commercial — in ways that rarely align so neatly.
The most consequential development was China's Breakthrough Therapy designation for ATG-022, an antibody-drug conjugate targeting CLDN18.2 in gastric and gastroesophageal junction cancers. What distinguished the Phase I/II data was not just the 40% response rate at the 2.4 mg/kg dose, or the 90% disease control rate, or the fact that 82.7% of patients were still alive at nine months — it was that the drug worked even in patients with low or ultra-low tumor expression of the target protein, a population typically excluded from such therapies. Three patients achieved complete remission across cohorts. Early signals from a gynecologic tumor basket cohort, where all seven evaluable patients showed shrinkage, hint that CLDN18.2 may be a productive target well beyond gastric cancer. Dose-expansion studies are now running in China and Australia across multiple treatment lines.
ATG-037, an oral CD73 inhibitor tested alongside pembrolizumab, delivered results in a population that oncology has struggled to serve: patients whose melanomas had become resistant to both anti-PD-1 and anti-CTLA-4 therapies. Among eleven such patients, 36.4% responded and all achieved disease control, with one patient in complete remission after more than 32 months on trial. In non-small cell lung cancer, responses were less frequent but proved similarly durable, with some patients stable for up to 28 months — suggesting the combination is sustaining benefit rather than producing brief, transient effects.
Beyond oncology, Antengene is preparing to enter autoimmune disease with ATG-201, a T-cell engager built on its proprietary AnTenGager platform. Primate studies showed the compound depletes B cells across multiple tissue compartments with minimal cytokine release — a critical safety threshold for this drug class. Human trials are expected to begin in the fourth quarter of 2025, and the company is actively seeking development partners for the broader platform.
Commercially, XPOVIO generated RMB 53.2 million in the first half of 2025, a 70.6% increase over the prior period, now approved across ten Asia-Pacific markets and reimbursed in Taiwan and for two indications in mainland China. A third Chinese indication for multiple myeloma was added in July. Strikingly, this revenue growth came alongside a 34% reduction in sales expenses and a 32.8% cut in administrative costs — a combination that points to genuine operational improvement. The company closed June with RMB 794 million in cash, which management described as sufficient to carry its key programs through proof-of-concept. CEO Jay Mei characterized the results as confirmation that clinical ambition and operational discipline can advance together.
Antengene, a Shanghai and Hong Kong-listed biotech company, reported interim results for the first half of 2025 that painted a picture of a firm hitting its stride across multiple fronts—clinical breakthroughs, regulatory wins, and commercial momentum all converging at once.
The headline achievement was the Breakthrough Therapy designation granted by China's National Medical Products Administration for ATG-022, an antibody-drug conjugate targeting CLDN18.2 in gastric and gastroesophageal junction cancers. The designation came on the back of Phase I/II data showing that the drug worked across the full spectrum of patient populations, regardless of how much of the target protein their tumors expressed. In patients with moderate-to-high expression levels, the 2.4 mg/kg dose achieved a 40 percent response rate—12 of 30 patients saw their tumors shrink—with a 90 percent disease control rate. Median progression-free survival reached 6.97 months, and 82.7 percent of patients were alive at nine months. Even in patients with low or ultra-low expression, the drug delivered a 33 percent response rate and 50 percent disease control. Three patients achieved complete remission across the different cohorts. This breadth of efficacy across expression levels is unusual and valuable; it suggests ATG-022 could become what the company calls a backbone therapy, usable in a wider patient population than many competitors.
The company is now running dose-expansion studies in mainland China and Australia, with plans to test the drug in first-, second-, and third-line settings, often in combination with other immunotherapies like pembrolizumab. Early data from a separate basket trial cohort hinted at potential beyond gastric cancer: all seven evaluable patients with a certain gynecologic tumor subtype showed tumor shrinkage, signaling that CLDN18.2 may be a target worth pursuing across multiple cancer types.
ATG-037, an oral CD73 inhibitor being tested alongside Merck's pembrolizumab, showed particularly striking results in patients whose tumors had become resistant to checkpoint inhibitors—a notoriously difficult population to treat. Among 11 melanoma patients, mostly with resistance to both anti-PD-1 and anti-CTLA-4 antibodies, the response rate was 36.4 percent, with complete disease control in all patients. One patient achieved a complete remission and remained on the trial for over 32 months. In the non-small cell lung cancer cohort, the response rate was lower at 21.4 percent, but disease control reached 71.4 percent, and responses proved durable, with some patients stable on treatment for 15 to 28 months. These durability figures matter because they suggest the combination is not just producing quick responses that fade.
The company is also expanding into autoimmune disease, a new therapeutic area for the firm. ATG-201, a T-cell engager developed on Antengene's proprietary AnTenGager platform, showed good tolerability in primate studies at multiple dose levels with minimal cytokine release—a major safety concern with this class of drug. The compound can deplete B cells across peripheral blood, spleen, and lymph nodes, and is expected to enter human trials in the fourth quarter of 2025. The platform itself, featuring what the company calls a "2+1" bivalent binding design and steric hindrance masking, is designed to work across autoimmune diseases, solid tumors, and blood cancers, and Antengene is actively seeking partnerships to develop it further.
On the commercial side, XPOVIO, the company's approved selinexor product, generated 53.2 million Chinese yuan in the first half of 2025, a 70.6 percent jump from the prior period. The drug, used for certain blood cancers, has now won approval in ten countries and regions across the Asia-Pacific region, with two of its three approved indications in mainland China already covered by national reimbursement. In July, it won a third indication for multiple myeloma in China. Taiwan approved it for reimbursement in February. Notably, the company cut sales and administrative expenses by 34 percent and 32.8 percent year-over-year, respectively, even as revenue climbed—a sign of improving operational discipline. As of June 30, the company held 794 million yuan in cash, enough, management said, to carry its key programs through proof-of-concept stages.
Founder and CEO Jay Mei framed the results as validation of a two-pronged strategy: innovation in the clinic and efficiency in operations. The next milestones to watch are the Phase II expansion data for ATG-022 in gastric cancer, the continued durability data from ATG-037 in checkpoint-inhibitor-resistant patients, and the first human safety and efficacy readouts from ATG-201 in autoimmune disease when that trial begins later this year.
Notable Quotes
ATG-022's distinctive characteristics as a potential backbone therapy for the treatment of gastric cancer— Jay Mei, Founder, Chairman, and CEO of Antengene
The responses demonstrated impressive durability, with patients remaining on trial for over 15 to 32 months— Antengene interim results statement on ATG-037 combination therapy
The Hearth Conversation Another angle on the story
Why does it matter that ATG-022 works across all expression levels of CLDN18.2?
Because most targeted drugs only work well in patients whose tumors have high levels of the target. If your tumor has low expression, the drug often fails. ATG-022 breaking that pattern means you're not excluding a large chunk of patients upfront. It's a commercial advantage and a medical one—more people can potentially benefit.
The melanoma data for ATG-037 looks strong, but the lung cancer numbers are lower. What's the difference?
Melanoma patients in that trial had been through both anti-PD-1 and anti-CTLA-4 drugs and still failed. They're a tougher population, but the combination worked better there. Lung cancer patients had different resistance patterns. It suggests the drug may have a sweet spot—certain tumor types or resistance profiles where it shines.
Why is moving into autoimmune disease significant for a cancer company?
It's a different market, different regulatory pathway, different patient population. But it's also a validation of their platform technology. If the same T-cell engager approach works for both cancer and autoimmune disease, that's a platform play, not a one-drug company. It de-risks the whole enterprise.
The cash position is 794 million yuan. Is that enough?
They say it's enough to take key programs to proof-of-concept. That's the inflection point where you know if something works. After that, you need more money or a partner. So they're buying time to prove the science, which is the smart play when you're not yet profitable.
What's the real story underneath the revenue growth for XPOVIO?
It's not just that sales went up 70 percent. It's that they did it while cutting costs by a third. That means the drug is gaining traction in the market, reimbursement is working, and they're not burning cash to get there. That's the kind of efficiency that keeps a biotech alive long enough to see its pipeline mature.